Does anyone have any strategies for maxing legendary drops?

My basic understanding is that, beyond maximizing SPECIAL, you want to get your dweller out 60 hours or so until they hit the National Guard Depot event. I believe you have to get to 60 before dying, or it resets, meaning, if a dweller dies at 59 hours (before the event), and you revive them, they have to make it another 60 hours before the event triggers, which means it's not going to happen since they have no stimpacks now.

Maximizing the chance to get to 60 hours/event seems to involve using the best weapon, and using an outfit that has S, P and A, L secondarily.

I have almost half my dwellers (90 or so) maxed SPECIAL with a variety of +5, +6 and +7 stat gear and weapons ranging from 16 to 24 out in the wastelands, and it has been two weeks since I got a single legendary item drop. With so many dwellers in the wasteland, managing them is an exercise in frustration, as the game will crash if I try to look at each dweller by tapping on the wasteland and tapping the arrow to move amongst them. What I do now is look at all dwellers, sort by job, and scroll down until I see someone dead. Revive them and bring them in. Similarly, trying to sell their loot when they arrive back crashes the game, so now I just collect everything and deal with it in the inventory screen.

I don't even know how to see whether any dweller in the wasteland even hit the event never mind what might have dropped for them, because as I said, if i try to look at a dweller's log, and scroll through it, it's laggy and likely to crash the game, and of course, the log only goes back a little ways.

Could I be wasting effort even having so many dwellers out there? Maybe the event can only fire once a day or something? With 90 dwellers out, you'd think I'd be swimming in legendaries; 60 hours is 2.5 days and most of my dwellers make it that far.

Edit: it appears that the National Guard Depot event has been nerfed into oblivion in the last patch, meaning, strategies around getting to it for legendaries are not going to work. Thanks Bethesda, if you nerfed this. Starting to wonder if the game is worth playing any more.

You can still get legendaries from the national guard depot, they just arent guaranteed and only a small chance (i at least get some rare weapons every time they hit it so far). But yes, it's not guaranteed, so the game favours quantity over quality. As in, having tons of explorers hit the national guard depot until you get a legendary.

My friend got one the other day, but so far i havent got a legendary from the guard depot. It's just really hard.

i like the challenge, my 60 explorers will have tough time finding good stuff

I sent 4 out just recently, only one made it past 50hours. He hit 72 hours then died. I couldn't read his posts around the 60hr mark as it wouldn't scroll back far enough so not sure if he hit the NCR base or not? I did end up with 3 legendary items but he had them when I went to bed at the 55hr mark.